Isotopic separation has been done in various manners, including fractional distillation, mass spectroscopy, and selective light absorption.
Isotope separation using lasers could produce large reductions in the cost of isotope production.
The use of lasers in isotopic separation has previously been attempted in methanol and in Br.sub.2. However, the kinetics of the prior-art systems were too complicated for clear interpretation of the results, or for the processes to be useful in actual production.
The essential ingredients for a scheme of isotope separation by lasers are:
1. An absorption spectrum with a well-resolved isotope shift,
2. A laser significantly monochromatic and tunable to excite the absorption of one isotope and not the other,
3. A chemical or physical process which acts on excited molecules and separates them from unexcited ones but need not have any inherent isotopic selectively, and
4. A set of photochemical rate constants and physical conditions such that energy transfer from a laser-excited species to an undesired species does not occur before the separation in ingredient (3) above.
These essential ingredients have been absent from the prior art. One purpose of the present invention is to render isotope separation by lasers and also similar photo-excitation feasible.
Some orders of magnitude may help to show that laser separation could have a revolutionary effect on isotope costs. Present isotope prices generally run between one hundred dollars and one hundred thousand dollars per mole. The power costs of using a laser method for separation would run about three dollars per mole, based on an assumption of a laser efficiency of 10.sup.-.sup.3 and employing that in a process yielding one separated atom for each 3300 A photon absorbed, which requires about one-tenth of one kilowatt hour of light per mole of product. Even though the power cost is not the total cost, nevertheless the differential is remarkable.